Moscow: Increased digital clutter, owing to an explosion in the usage of apps, is leaving smartphones vulnerable to security threats, a new survey said on Monday.

Conducted by cyber security firm Kaspersky Lab across 17 countries, it showed that users typically install 12 Android apps every month but delete only 10, in effect adding two apps to their device on a monthly basis.

With more apps installed on devices, managing apps is important in preventing digital clutter.

However, only half (55 per cent) of the users regularly refresh and revise the contents of their device and delete unused documents and apps.

"Users are exposing devices and personal data to security threats by failing to undertake simple but essential care for their device that cleans and updates software and apps, adjusts settings and uninstalls apps that are no longer used," said Andrei Mochola, head of Consumer Business at Kaspersky Lab.

In a quarter of cases (28 per cent), users only update apps on their devices when they are forced to, and in 10 per cent of cases they try not to do it at all.

Not known to many, apps can also operate without user permission, the researchers said.

In the study, when a representative sample of 66 of the most popular Android apps was tested, 54 launched in the background without users even touching them and consuming, on average, 22 MB traffic per day without any user interaction.

While the app settings can give users a degree of control over what the app can access and interact with on the device, only 40 per cent of people were found to intentionally adjust the settings on their smartphone.

"The build-up of digital clutter can also lead to a wide range of problems such as device glitches, battery life issues or malware infection," the researchers noted.